yep, weird it is. some user said it might be case sensitive. the only thing that worked for me was, when i copied the files of an PC save (not the whole folder) into an exisiting folder of saves on the switch, that i created through JKSV in before and let it overwrite any file. it didn't work if i made a new folder or only copied the .sav
however it only works from pc to switch. i can't get it to work from switch to pc. neither the game nor KSE can load the files. that sucks.